[@VitaVitaAR] I guess I would say it's because they're so baffling and exotic that he's the only one who has figured out how to activate them. He may have some strange connection to them related to his "delusions" about gods and what have you.

To give you an idea of what I mean, I was thinking that one of his artifacts creates a tiny portal that one or more large tentacles would then erupt out of, which he has a moderate degree of control over.